A Spiking Neuron Model of the Basal Ganglia Circuitry that Can Generate Behavioral Variability
ABSTRACT The cortical-basal ganglia circuitry has been implicated in action selection, action initiation, and generation of behavioral
variability. However, underlying mechanisms for these functions still remain unresolved. In this paper, we propose a new spiking
neuron model for the basal ganglia circuitry that includes different functions for the direct and indirect pathways: the indirect
pathway selects an action to be executed and then the direct pathway determines the timing of the selected action. Computer
simulations demonstrate that the basal ganglia circuitry supports action selection and self-timed initiation of actions. The
circuitry can also generate trial-by-trial variations in the selection and timing of actions for exploration. Finally, these
variations can optimally and independently be tuned by the strength of corticostriatal synapses for exploitation.